Connector for a circuit card having means for forcing spring contacts into contact with the card after the card is put in position

ABSTRACT

A connector for a circuit card comprises a connector block having spring contacts arranged in two rows and a connector housing removably engaging with the block. The card is supported by the housing and put in position, extending into the block between the spring contact rows, after the housing is brought into engagement with the block. The housing comprises lock means for keeping the spring contacts away from and forcing them into contact with the card before and after the card is put in position, respectively.

' United States Patent Kasuya et al.

CONNECTOR FOR A CIRCUIT C RI) HAVING MEANS FOR FORCING SPRING CONTACTSINTO CONTACT WITH THE CARD AFTER THE CARD IS PUT IN POSITION lnventors:Hiroshi Kasuya; Norio Watanabe,

Assignee:

Filed:

App]. No.2

both of Tokyo, Japan Nippon Electric Company, Ltd., Tokyo, Japan May13,1974

Foreign Application Priority Data May11,1973 Japan 48-52795 US. Cl.....

References Cited UNITED STATES PATENTS Vanderpool 339/75 MP MP;211/41;317/101 DH;

339/112 R; 339/176 MP Int. Cl. .fi H01R 13/54 Field of Search 339/17,75, 112, 176; 211/41; 317/101 DH 2,940,017 6/1960 Murphy et a1. 339/17LM 3,245,546 4/1966 Stuhler 21 1/41 3,474,387 lO/l969 Krum et a1. 339/75MP 3,550,062 12/1970 Drenten et a1. 339/75 MP 3,710,303 1/1973 Gallager,Jr 339/75 MP 3,753,211 8/1973 Pauza et a1 339/75 MP PrimaryExaminer.1oseph H. McGlynn Attorney, Agent, or Firm-Sughrue, Rothwell,Mion, Zinn & Macpeak ABSTRACT A connector for a circuit card comprises aconnector block having spring Contacts arranged in two rows and aconnector housing removably engaging with the block. The card issupported by the housing and put in position, extending into the blockbetween the spring Contact rows, after the housing is brought intoengagement with the block. The housing comprises lock means for keepingthe spring contacts away from and forcing them into Contact with thecard before and after the Card is put in position, respectively.

10 Claims, 6 Drawing Figures US. Patent 0C1. 14, 1975 Sheet 1 of 33,912,353

US. Patent Oct.14,1975 Sheet2of3 3,912,353

U.S. Patent Oct. 14, 1975 Sheet 3 of3 3,912,353

FIG. 6

CONNECTOR FOR A CIRCUIT CARD HAVING MEANS FOR FORCING SPRING CONTACTSINTO CONTACT WITH THE CARD AFTER THE CARD IS PUT IN POSITION BACKGROUNDOF THE INVENTION This invention relates to a connector for a circuitcard, such as a ceramic substrate having at least one large-scaleintegrated circuit placed thereon and a plurality of leads or electricconductors leading thereto formed on the substrate.

On mounting a circuit card on a main plugboard or patchboard, such asprinted circuit board, it has been the practice to resort to solderingor similar process for providing semipermanent electric connectionsbetween the card and the board, or more particularly, between theelectric conductors of the former and like conductors of the latter. Onthe other hand, large scale integrated circuits have come into use inelectronic computers and other apparatus in order to raise thereliability of the latter. It has therefore become necessary to providereadily disconnective electric connections, with the use of connectors,betweenthe card and board to enable rapid replacement of the card whenoperation of the integrated circuit is put in disorder.Conventionalconnectors for the large-scale integrated circuit cards,however, are of the sophisticated edge connector type and exhibit thefollowing defects upon insertion and removal of the card into and fromthe connector.

(l) The substrate of a large-scale integrated circuit card is usuallymade of a mechanically weak ceramic or similar material and is oftenbroken. (2) In order to insure the reliability of electric connection,the spring contacts of the connector must be forced into contactwith-the card under an appreciable pressure. The electric conductorsformed on the substrate are therefore subject to damages. Particularly,such damages are liable to occur at the terminal areas of the card whichare surfacetreate'd in order toprovide excellent electric connections.(3) Predetermined portions of the spring contacts are alsosurface-treated in order to insure electric connections. On the otherhand, the substrate has sharp edges and is harder than thesurface-treated portions. The substrate consequently often damages thesurface-treated portions of the spring contacts particularly oninserting the card into the connector. (4) The card is manually handledon putting the card into and away from the connector. This very likelystains and damages the large-scale integrated circuit of the card.

Attempts for removing the above-mentioned and similar defects havemainly been directed to the electric conductors formed on the substrate.However, the attempts are thus far not'satisfactory in that thelargescale integrated circuits are not sufficiently protected.

Connectors for circuit cards, other than the largescale integratedcircuit cards, have like defects.

SUMMARY OF THE INVENTION It is therefore an object of the presentinvention to provide a connector for a circuit card having a connectorblock and a removably engaging connector housing wherein spring contactsof the connector are not brought into substantial contact with the cardduring the operation of bringing the block and housing into engagementwith and disengagement from each other.

It is another object of this invention to provide a connector of thetype described, capable of minimizing the undesirable chances ofstaining and damaging the card during mounting the card on theconnector.

It is still another object of this invention to provide a connector ofthe type described, that will not be damaged by the card during theabove-mentioned operation.

It is a subordinate object of this invention to provide a connector ofthe type described, with which it becomes unnecessary to resort tospecific measures for protecting electric conductors formed on asubstrate of the card against failures.

A connector for a circuit card includes a connector block having a pairof side walls defining a card channel for freely slidably receiving thecard until an edge of the card reader reaches the bottom of the channel.The connector block further has a plurality of spring contacts disposedalong the respective side walls. The connector further comprises aconnector housing adapted for removable engagement with the connectorblock. In accordance with this invention, the connector housingcomprises a locking portion and a card supporting portion made integralwith the locking portion. The locking portion has a pair of side wallsdefining an opening for snugly receiving the connector block side wallsand freely receiving, during a first stage of the above-mentionedengagement, the spring contacts. Each of the connector housing sidewalls has an inwardly directed surface. The card supporting portion hasspring means and a pair of opposing guide channels for freely slidablyguiding the card. The spring means urges the above-mentioned edge of thecard guided along the guiding channels towards end faces of the lockingportion side walls that are remote from the card supporting portionwhereby the card is held by the housing. The guide channels are broughtinto registration with the card channel in the direction of thethickness of the card held by the housing during and after theabove-mentioned first stage. On the other hand, each of the springcontacts has a first bend projecting inwardly towards the card channeland a second bend protruding outwardly of the associated connector blockside wall. The opposing first bends of the spring contacts allow freeslide therebetween of the card held by the housing during theabove-mentioned first stage and a subsequently following second stage ofthe above-mentioned engagement, during which second stage theabovementioned edge of the card held by the housing reaches the bottomof the card channel. The inwardly directed surfaces come into contactwith and subsequently into sliding touch with the second bends prior tothe abovementioned second stage. Eventually, the inwardly directedsurfaces force the first bends into contact with the card held by thehousing after the second stage and when the housing and block arebrought into full engagement with each other.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 schematically shows aperspective view of four connectors according to a first embodiment ofthe instant invention together with circuit cards held by the connectorsand a circuit board to which electric connections are provided by theconnectors from the cards, one of the connectors having its connectorhousing removed and another having the connector housing partly cutaway;

FIG. 2 is an enlarged fragmentary cross-sectional view of a connectordepicted in FIG. 1;

FIG. 3 shows a perspective view of a connector housing of a connectorshown in FIG. 1, on a reduced scale together with a circuit card andwith parts broken away;

FIG. 4 shows an enlarged partial cross-sectional view of a connectorillustrated in FIG. 1 with the connector housing brought into partialengagement with a connector block of the connector;

FIG. 5 is a like view of the connector with the connector housingbrought into full engagement with the connector block; and

FIG. 6 is a perspective view of connector blocks of several connectorsaccording to a second embodiment of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 through 3,a connector for a circuit card 11 according to a first embodiment of thepresent invention is for disconnectively forming electric connectionsbetween terminal areas 12 (FIG. 3) of the card 11 and printed conductors(not shown) of a printed circuit board 16. The connector comprises aconnector block 21 and a connector housing 22 adapted for removableengagement with the connector block 21.

Referring more particularly to FIGS. 1 through 3, the connector block 21includes a pair of side walls 31 defining a card channel 32 for freelyslidably receiving the card 11 until an edge 33 (FIG. 3) of the card 11reaches a bottom 34 (FIG. 2) of the channel 32. In the example beingillustrated, each side wall 31 is formed of a plurality of protrusionsextending from a base 35 (FIG. 2) of the block Zl. The side walls 31 andthe base 35 may be made of a synthetic resin by molding. The connectorblock 21 further comprises a plurality of spring contacts 36 disposedalong the respective side walls 31 between the adjacently alignedprotrusions. The spring contacts 36 may be made of phosphor bronze,beryllium copper, or a similar electroconductive resilient material. Inthe example being illustrated, each spring contact 36 has a contact tailon tip 37 planted in the base 35 and extended through the printedcircuit board 16 to be soldered or otherwise mechanically andelectrically connected to pertinent one of the printed circuits (notshown) as best illustrated in FIG. 2. The side walls 31 have taperedportion 38. In accordance with this invention, each spring contact 36has a first bend 41 (FIG. 2) projecting inwardly towards the channel 32,a second bend 42 protruding outwardly of the tapered portion 38 of theassociated side wall 31, and a free end 43 extending from the secondbend 42 back toward a slit formed between the adjacently alignedprotrusions of the relevant side wall 31. It will be seen from FIG. 2that the opposing first bends 41 of the spring contacts 36 do notprotrude into the channel 32 to allow free slide therebetween of thecard 11 and that the tapered portions 38 of the side walls 31 areapproximately equally sloped as the free ends 43 .of the spring contacts36 and then extended without materials taper towards free ends of theside walls 31. In this manner known in the art, at least inwardlydirected surfaces of the first bends 41 are plated with gold orotherwise surface-treated to provide best possible electric contact withthe terminal areas 12 of the card 11 which are similarlysurface-treated.

Referring specifically to FIGS. 1 through 3 and referring to FIGS. 4 and5, the connector housing 22 comprises a locking portion 46 and a cardsupporting portion 47. These portions 46 and 47 may be integrally madeof a synthetic resin. Alternatively, the card supporting portion 47 maybe possessed of a back plate 48 made of a thermally conductive metal inorder to serve as a heat sink for the card 11. The card supportingportion 47 having a metal back plate 48 should be integrally united witha synthetic resin locking portion 46 by means of machine screws 49 or byany other means. The locking portion 46 has a pair of side wallsdefining an opening for snugly receiving the connector block side walls31 and freely receiving, in a first stage of bringing the housing 2 andblock 21 into engagement with each other, the spring contacts 36 as bestshown in FIG. 4. Each of the connector housing side walls has aninwardly directed surface 51 (FIG. 4) and an end face 52 that is remotefrom the card supporting portion 47. The card supporting portion 47 hasa pair of opposing guide channels 56 and 57 (FIG. 3) for freely slidablyguiding the card 11 and spring means that comprises, in turn, a leafspring 58 and a boss 59 either fixed or removably attached to atransverse member, such as the back plate 48, extending between theguide channels 56 and 57 in offset relation thereto in the adjacency ofthe free end of the card supporting portion 47. The spring means urgesthe above-mentioned edge 33 of the card 11 sliding along the guidechannels 56 and 57 towards the end faces 52 of the locking portion sidewalls, whereby the card 1 1 is held by the connector housing 22.Preferably, a pair of narrow walls, such as 61, interconnecting thelocking portion side walls is provided with a pair of end shoulders,such as 62, for insuring holding of the card 11 by the connector housing22 even when the latter is disengaged from the connector block 21. Inother words, the end shoulders 62 enable the connector housing 22 easilyself-support the card 11. The guide channels 56 and 57 should be broughtinto registration with the card channel 32 at least in the direction ofthe thickness of the card 11 held by the housing 22 when the housing 22and block 21 are brought into engagement with each other. Preferably,the guide channels 56 and 57 are left open at their ends remote from theend faces 52 of the connector housing side walls. It will be noticedthat the inwardly directed surfaces 51 of the connector housing sidewalls are approximately equally sloped as the free. ends 43 of thespring contacts 36 and then extended substantially parallel to the guidechannels 56 and 57. It is preferred that second bends 42 be firstbrought into contact with the inwardly directed surfaces 51.

Referring specifically to FIG. 4, the locking portion 46 may have a pairof shoulder walls 66 extending inwardly from the locking portion sidewalls to define a card slot 67 in registration with the guide channels56 and 57. It will be noticed that the card 11 shown here has theterminal areas 12 on both principal surfaces of the substrate. The card11, however, may have the terminal areas 12 on only one of the principalsurfaces of the substrate. In the latter case, the card supportingportion 47 may have two pairs of juxtaposed guide channels, such as 56,on both sides of the back plate 48 or other transverse member, whichguide channels are brought in combination into registration with thecard channel 32 at least in the direction of the thickness of the cards,such as '11, when the housing 22 and block 21 are brought intoengagement with each other.

Referring back and more particularly to FIG. 3, the card 11 may bemounted on the connector housing 22 by removing the dismountable springmeans, such as 58 and 59, and by letting the card 11 slide into theguide channels 56 and 57 with the above-mentioned edge 33 of the card 11having the terminal areas 12 therealong first into the open ends of theguide channels 56 and 57. Subsequently put in position, the card 11 isurged by the spring means 58 and 59 against the end shoulders 62 to beself-supported by the 'housing 22. Removal of the card 11 from thehousing 22 would be selfexplanatory. I

Referring again and more particularly to FIG. 4, the connector housing22 with the card 11 is now put into partial engagement with theconnector block 21. At a first stage of the engagement, the openingdefined by the connector housing side walls snugly receives theconnector block side walls 31 and freely receives the spring contacts36. As has already been mentioned, the guide channels 56 and 57 arebrought into registration with the card channels 32. The opposing firstbends 41 of the spring contacts 36 allow free slide therebetween of thecard 11 held by the housing 22. At a subsequently following second stageof the engagement illustrated in FIG. 4, the above-mentioned edge 33 ofthe card 11 held by the housing 22 reaches the bottom 34 of the cardchannel 32. Either at this second stage or soon thereafter, the inwardlydirected surfaces 51 of the connector block side walls 31 come intocontact with the second bends 42 of the spring contacts 36 andsubsequently into sliding touch therewith. It should specifically bepointed out that the spring contacts 36 are left free until the card 11is put in position where the above-mentioned edge 33 of the card 11reaches the bottom 34 of the card channel 32.

Referring now specifically to FIG. 5, the connector housing and block 22and 21 are brought into full engagement with each other from the secondstage illustrated with reference to FIG. 4. The second bends 42 of thespring contacts 36 have slidden along the inwardly directed surfaces 51of the connector housing side walls until the inwardly directed surface51 eventually force the first bends 41 of the spring contacts '36 intomechanical and electric contact with the terminal areas 12 of the card11 that has already been put in the above-mentioned position. It isworthwhile to note that the contact of the first bends 41 to theterminal areas 12 or, roughly spoken, the card 11 occurs without anyrelative slide therebetween after the second stage of the engagement andthat the engagement is carried out without direct touch to the card 11.Incidentally, the card 11 may slide relative to the housing 22 along theguide channels, such as 56, against the action of the spring means 58and 59 (FIG. 3) so that the edge 33 may come out of contact with the endshoulder 62 (FIG. 3) either immediately before the second stage or asthe engagement is brought from the second stage to the full engagement.

Reviewing FIGS. 4 and 5, operation ofthe connector according to thisinvention during relative disengagement of the connector housing 22 fromthe connector block 21 will be self-explanatory. It should, however, beagain pointed out that no direct manual touch to the card 11 isunnecessary and that no slide occurs between the spring contacts 36 andthe card 11.

Referring finally to FIG. 6, a connector according to a secondembodiment of this invention makes use of the printed circuit board 16as the base 35 (FIG. 2) of the connector block 21. More particularlyreferring to part (A) of FIG. 6, the contact tips 37 of a plurality ofspring contacts 36 are put through pertinent ones of holes 71 formedthrough the board 16 in a regular array and fixed to the board 16. Asshown in part (B), a side wall block 72 having side wall protrusions 73in correspondence to the holes 71 is put on the board 16 so that thespring contacts 36 may extend between relevant portions of the side wallprotrusions. In part (C), the side wall block 72 is fixed to the board16 by means of machine screws (not shown) put through holes 74 therefor,by the use ofa bonding agent, or by any other means. With thisembodiment, it is possible to put the spring contacts 36 into the boardholes 71 by means of a numerically controlled automatic machine. It isalso possible. to dip the board 16 having the spring contacts 36 putthrough the holes 71 as illustrated in part (A) in a solder bath tocarry out the soldering. It is thus feasible to speed up themanufacture. In addition, it is easy to substitute a new spring contactfor any one of the spring contacts 36 that may happen to be damaged.

With a conventional connector of the type described, the characteristicsand reliability were degraded after about 50 times of connection anddisconnection between an integrated circuit card and a printed circuitboard. In contrast, the characteristics and reliability were notobjectionably degraded with a connector according to this inventionuntil about two hundred times of connection and disconnection. It hasbeen necessary with a conventional connector to use a gold layer of athickness between 15 and 20 microns for the terminal areas 12 of thecard 11 and the spring contacts 36. In contrast, the thickness may beonly 2 to 3 microns for a connector according to this invention. Thisconsiderably saves the cost of manufacture.

While the invention has been described in detail and with reference tospecific embodiments thereof, it will be apparent to one skilled in theart that various changes and modifications can be made therein withoutdeparting from the spirit and scope thereof.

We claim:

1. A connector for electrically connecting a printed circuit card havinga plurality of contacts adjacent one edge of said card to a main printedcircuit board comprising;

a. at least one connector block having a base portion affixed to saidmain printed circuit board, a slot to receive a printed circuit card,and a portion of reduced width opposite said base portion adjacent saidcard receiving slot;

b. a plurality of electrical spring contacts protruding through saidconnector block base portion on each side of said card receiving slot,said spring contacts having one end in electrical contact with said mainprinted circuit board, each of said electrical spring contacts having afirst portion projecting inwardly towards said card receiving slot, asecond portion projecting outwardly laterally beyond said reduced widthportion of said connector block and a third portion projecting inwardlytoward said card receiving slot at an angle to the central axis of saidcard receiving slot, such that no portion of said electrical springcontacts extend into said card slot in said connector block; c.,printedcircuit card holding means allowing manual handling of said card withoutphysically touching the card itself; and v I v d. housing means attachedto said card holding means and releasably attachable to said connectorblock means to deform said electrical spring contacts into the slot insaid connector Board and, hence, into contact with said card after saideard has been inserted into said slots by the-card holding means. I p,2. The connector of clairn 1 wherein said housing means has an openingdefined by side, top,and bottom walls, a first portion of theinnersurface ,of said, side walls contacting the base portionof saidconnector block, a second portion of the inner surfaceof said side wallshaving a wedge portion protruding inwardly so as to engage said thirdportion of said electrical spring contacts. 1 I I 3. The connector ofclaim 2 wherein the angle of said wedge portion is the same as the angleof the third portion of said electrical spring contacts. a I

4. The connector of claim 2 wherein said printed circuit cardholdingmeans comprises a pair of members having a generally'U-shapedcross section, said members engaging opposite sides of said card andhaving one end attached to said housing means.

5. The connector of claim 4 wherein a back plate connects correspondinglegs of said U-sh aped me m- 'bers.

6. The connector of claim 4wherein said back plate is'composed of metalhaving high thermal conductivity and is in contact'with said printedcircuit card.

7. The connector of claim 4 wherein spring means attached to said backplate contacts one edge of said card toui'ge said card' toward saidhousing' means.

84A connector for electrically connecting a printed circuit card havinga plurality of contacts adjacent 'one edge of said card toa main printedcircuit board comprising:

a. at least one elongated connector block having a base portion affixedto said main printed circuit board, said connector block having a slotextending centrally and lengthwise thereof and having a width to receivea printed circuit card;

b. a plurality of electrical spring contacts protruding through saidconnector block base portion on each side of said card receiving slot,each of said spring contacts having one end in electrical contact withsaidmain printing circuit board, a first portion adjacent said cardreceiving slot projecting inwardly towards said slot, and a secondportion adjacent the distal end bent so as to protrude laterally beyondsaid connector block, said contacts being positioned such that noportion extends into said card receiving slot; and c. a connectorhousing comprising a card supporting portion having a pair of members,each having a pair of legs defining a guide channel for slidably guidingsaid printed circuit card, said guide channel being substantially equalin width to the width of said card receiving slot, a back plateconnecting corresponding legs of said members, and spring means mountedon said back plate, said housing being releasably attachable to saidconnector block to push said electrical springcontacts at the secondportions to urge the first portions into said card receiving slot withthe guide channels brought into substantial alignment with said cardreceiving slot, said spring means urging said printed circuit into saidcard receiving slot when the housing is attached to said connectorblock, whereby said electrical spring contact second portions arebrought into electrical contact with said contacts of said printedcircuit card after said card has been pushed into said card receivingslot with substantially no force exerted perpendicularly of said printedcircuit card. 9. The connector of claim 8 wherein said connector blockcomprises a pair of side walls defining said card receiving slot, the]second portions of said electrical spring contacts protruding laterallyoutwardly of said connector block side walls, and wherein said connectorhousing comprises a pair of side walls defining an openingfor releasablyand snugly receiving said connector said guide channels by said springmeans.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTIONPATENT NO. 3912353 DATED October 14, 1975 INVEN I I-Iiroshi Ka suya,Norio Watanabe it is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

IN THE SPECIFICATION:

Column 1, line 19 Insert hyphen in large scale" line 41 insert hyphen in"surface-treated Column 2, line 51 insert hyphen in "above mentioned"line 55 e insert hyphen in above mentioned" Column 3, line 66 delete"materials" and insert -=-material=-- line 67 after "In" delete "this"and insert --the-- Column 4, line 18 delete "Z" and insert ZZ- Column 5,line 44- delete "slidden" and insert --slid-- Column 6, line I delete"unnecessary" and insert =-necessary-- IN THE CLAIMS:

Column 8, line 2 delete "printing circuit board" and insert --printedcircuit board-- line 22 after "circuit" insert card Signed and Sealedthisthirtieth D ay of March 1 976 [SEAL] A ttest:

RUTH C. MASON C. MARSHALL DANN Afrrsling Offittr ('nmmixsiuner oflatentsand Trademarks UNITED STATES PATENT AND TRADEMARK OFFICE EERTIFICATE 0FCORRECTIQN PATENT NO. I 3912353 [)PJtD October 14, I975 ENVENIORI l IHiroshi Kasuya, Norio Watanabe !t is certified that error appears in theabove-identified patent and that said Letters Patent an: herebyrig-treated as shown below;

IN THE SPECIFICATION:

Column 1, line 19 Insert hyphen in "large scale" line 41 H insert hyphenin "surface-Created Q Column 2, line 51 insert hyphen in "abovementioned" line 55 e insert hyphen in "above mentioned" Column 3, line66 delete "materials" and insert --material=- line 67 after "In" delete"this" and insert --the=-- Column 4, line 18 e delete "Z" and insert-ZZ-W- Q Column 5,, line 44- delete "slidden" and insert =--slid---Column 6, line 1 delete "unnecessary" and insert necessary- IN THECLAIMS:

Column 8, line 2 delete "printing circuit board" and insert -printedcircuit board-- line 22 after "circuit" insert card Signed and Scaledthis thirtieth Day of March 1976 [SEAL] Arrest.

RUTH C. MASON C. MARSHALL DANN Arlesling Officer (ommissinner ufParenrsand Trademarks UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OFCORRECTION PATENT NO. I 3912.353

DATED October 14, 1975 INVENTQW I Hiroshi Ka suya, Norio Watanabe it iscertified that error appears in the above-identified patent and thatsaid Letters Patent arr;- iiereby corrected as shown below:

IN THE SPECIFICATION:

Column 1, line 19 Insert hyphen in "large scale" line 41 insert hyphenin "surfacetreated Column 2, line 51 insert hyphen in "above mentioned"line 55 insert hyphen in "above mentioned" Column 3, line 66 delete"materials" and insert -=-material=- line 67 after "In" delete "this"and insert --the-=-- Column 4, line 18 delete "Z" and insert =-22--Column 5, line 44-- delete "slidden" and insert slid- Column 6, line 1delete "unnecessary" and insert =-necessary-- IN THE CLAIlVlS:

Column 8, line 2 delete "printing circuit board" and insert --printedcircuit board-- line 22 after "circuit" insert card Signed and Scaledthis thirtieth D f March 1976 [SEAL] Attest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ofParenrsand Trademarks

1. A connector for electrically connecting a printed circuit card having a plurality of contacts adjacent one edge of said card to a main printed circuit board comprising; a. at least one connector block having a base portion affixed to said main printed circuit board, a slot to receive a printed circuit card, and a portion of reduced width opposite said base portion adjacent said card receiving slot; b. a plurality of electrical spring contacts protruding through said connector block base portion on each side of said card receiving slot, said spring contacts having one end in electrical contact with said main printed circuit board, each of said electrical spring contacts having a first portion projecting inwardly towards said card receiving slot, a second portion projecting outwardly laterally beyond said reduced width portion of said connector block and a third portion projecting inwardly toward said card receiving slot at an angle to the central axis of said card receiving slot, such that no portion of said electrical spring contacts extend into said card slot in said connector block; c. printed circuit card holding means allowing manual handling of said card without physically touching the card itself; and d. housing means attached to said card holding means and releasably attachable to said connector block means to deform said electrical spring contacts into the slot in said connector board and, hence, into contact with said card after said card has been inserted into said slots by the card holding means.
 2. The connector of claim 1 wherein said housing means has an opening defined by side, top and bottom walls, a first portion of the inner surface of said side walls contacting the base portion of said connector block, a second portion of the inner surface of said side walls having a wedge portion protruding inwardly so as to engage said third portion of said electrical spring contacts.
 3. The connector of claim 2 wherein the angle of said wedge portion is the same as the angle of the third portion of said electrical spring contacts.
 4. The connector of claim 2 wherein said printed circuit card holding means comprises a pair of members having a generally U-shaped cross section, said members engaging opposite sides of said card and having one end attached to said housing means.
 5. The connector of claim 4 wherein a back plate connects corresponding legs of said U-shaped members.
 6. The connector of claim 4 wherein said back plate is composed of metal having high thermal conductivity and is in contact with said printed circuit card.
 7. The connector of claim 4 wherein spring means attached to said back plate contacts one edge of said card to urge said card toward said housing means.
 8. A connector for electrically connecting a printed circuit card having a plurality of contacts adjacent one edge of said card to a main printed circuit board comprising: a. at least one elongated connector block having a base portion affixed to said main printed circuit board, said connector block having a slot extending centrally and lengthwise thereof and having a width to receive a printed circuit card; b. a plurality of electrical spring contacts protruding through said connectoR block base portion on each side of said card receiving slot, each of said spring contacts having one end in electrical contact with said main printing circuit board, a first portion adjacent said card receiving slot projecting inwardly towards said slot, and a second portion adjacent the distal end bent so as to protrude laterally beyond said connector block, said contacts being positioned such that no portion extends into said card receiving slot; and c. a connector housing comprising a card supporting portion having a pair of members, each having a pair of legs defining a guide channel for slidably guiding said printed circuit card, said guide channel being substantially equal in width to the width of said card receiving slot, a back plate connecting corresponding legs of said members, and spring means mounted on said back plate, said housing being releasably attachable to said connector block to push said electrical spring contacts at the second portions to urge the first portions into said card receiving slot with the guide channels brought into substantial alignment with said card receiving slot, said spring means urging said printed circuit into said card receiving slot when the housing is attached to said connector block, whereby said electrical spring contact second portions are brought into electrical contact with said contacts of said printed circuit card after said card has been pushed into said card receiving slot with substantially no force exerted perpendicularly of said printed circuit card.
 9. The connector of claim 8 wherein said connector block comprises a pair of side walls defining said card receiving slot, the second portions of said electrical spring contacts protruding laterally outwardly of said connector block side walls, and wherein said connector housing comprises a pair of side walls defining an opening for releasably and snugly receiving said connector block side walls, said opening communicating with the guide channels, said housing side walls being capable of pushing said electrical spring contacts at said second portions to urge the first portions into said card receiving slot as the side walls of said connector are received in said opening.
 10. The connector of claim 8 wherein said connector housing comprises shoulder means at the ends of said guide channels remote from said spring means for receiving the printed circuit board urged thereto along said guide channels by said spring means. 